It has been conventionally known that an audio signal processing device for processing audio signals in a plurality of channels (ch), such as a digital mixer and the like, has a function of allowing a user to select any channel to monitor the audio signal of the selected channel (see NPL1). Such a function is called a cue function.
Then, in the case of providing the cue function, a dedicated mixing bus, referred to as a “cue bus”, is provided for producing an audio signal for the monitoring. In the cue bus, the audio signal in the channel selected by the user is mixed, and then the resultant audio signal is outputted to a monitor terminal.